unfortunately, it is so. Like you read, there are threads about this. Many people are not happy. It is only an issue with the Ti with 18 inch wheels as far as I know. I bought the Ford cargo mat for my SEL sedan with subwoofer (I have 17 inch wheels with a donut spare) and the cargo mat fits absolutely perfectly.

Good luck with your fight, it is going to be an uphill battle for sure.